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Theorem abianfplem 3961
Description: Lemma for abianfp 3962. We prove by transfinite induction that if F has a fixed point x, then its iterates also equal x. This lemma is used for the "trivial" direction of the main theorem.
Hypotheses
Ref Expression
abianfp.1 |- A e. V
abianfp.2 |- G = rec({<.z, w>. | w = (F` z)}, x)
Assertion
Ref Expression
abianfplem |- (v e. On -> ((F` x) = x -> (G` v) = x))
Distinct variable groups:   x,v,A   x,z,w,F,v   v,G

Proof of Theorem abianfplem
StepHypRef Expression
1 fveq2 3724 . . 3 |- (v = (/) -> (G` v) = (G` (/)))
21eqeq1d 1483 . 2 |- (v = (/) -> ((G` v) = x <-> (G` (/)) = x))
3 fveq2 3724 . . 3 |- (v = y -> (G` v) = (G` y))
43eqeq1d 1483 . 2 |- (v = y -> ((G` v) = x <-> (G` y) = x))
5 fveq2 3724 . . 3 |- (v = suc y -> (G` v) = (G` suc y))
65eqeq1d 1483 . 2 |- (v = suc y -> ((G` v) = x <-> (G` suc y) = x))
7 abianfp.2 . . . . 5 |- G = rec({<.z, w>. | w = (F` z)}, x)
87fveq1i 3725 . . . 4 |- (G` (/)) = (rec({<.z, w>. | w = (F` z)}, x)` (/))
9 visset 1813 . . . . 5 |- x e. V
109rdg0 3941 . . . 4 |- (rec({<.z, w>. | w = (F` z)}, x)` (/)) = x
118, 10eqtr 1495 . . 3 |- (G` (/)) = x
1211a1i 8 . 2 |- ((F` x) = x -> (G` (/)) = x)
13 fvex 3732 . . . . 5 |- (F` (G` y)) e. V
14 ax-17 971 . . . . . 6 |- (u e. x -> A.z u e. x)
15 ax-17 971 . . . . . 6 |- (u e. y -> A.z u e. y)
16 ax-17 971 . . . . . . 7 |- (u e. F -> A.z u e. F)
17 hbopab1 2813 . . . . . . . . . 10 |- (u e. {<.z, w>. | w = (F` z)} -> A.z u e. {<.z, w>. | w = (F` z)})
1817, 14hbrdg 3936 . . . . . . . . 9 |- (u e. rec({<.z, w>. | w = (F` z)}, x) -> A.z u e. rec({<.z, w>. | w = (F` z)}, x))
197, 18hbxfr 1563 . . . . . . . 8 |- (u e. G -> A.z u e. G)
2019, 15hbfv 3729 . . . . . . 7 |- (u e. (G` y) -> A.z u e. (G` y))
2116, 20hbfv 3729 . . . . . 6 |- (u e. (F` (G` y)) -> A.z u e. (F` (G` y)))
22 fveq2 3724 . . . . . 6 |- (z = (G` y) -> (F` z) = (F` (G` y)))
2314, 15, 21, 7, 22rdgsucopab 3946 . . . . 5 |- ((y e. On /\ (F` (G` y)) e. V) -> (G` suc y) = (F` (G` y)))
2413, 23mpan2 696 . . . 4 |- (y e. On -> (G` suc y) = (F` (G` y)))
25 fveq2 3724 . . . . 5 |- ((G` y) = x -> (F` (G` y)) = (F` x))
26 id 59 . . . . 5 |- ((F` x) = x -> (F` x) = x)
2725, 26sylan9eqr 1529 . . . 4 |- (((F` x) = x /\ (G` y) = x) -> (F` (G` y)) = x)
2824, 27sylan9eq 1527 . . 3 |- ((y e. On /\ ((F` x) = x /\ (G` y) = x)) -> (G` suc y) = x)
2928exp32 377 . 2 |- (y e. On -> ((F` x) = x -> ((G` y) = x -> (G` suc y) = x)))
30 visset 1813 . . . . . . . 8 |- v e. V
31 rdglim2a 3950 . . . . . . . 8 |- ((v e. V /\ Lim v) -> (rec({<.z, w>. | w = (F` z)}, x)` v) = U_y e. v (rec({<.z, w>. | w = (F` z)}, x)` y))
3230, 31mpan 695 . . . . . . 7 |- (Lim v -> (rec({<.z, w>. | w = (F` z)}, x)` v) = U_y e. v (rec({<.z, w>. | w = (F` z)}, x)` y))
337fveq1i 3725 . . . . . . 7 |- (G` v) = (rec({<.z, w>. | w = (F` z)}, x)` v)
347fveq1i 3725 . . . . . . . . 9 |- (G` y) = (rec({<.z, w>. | w = (F` z)}, x)` y)
3534a1i 8 . . . . . . . 8 |- (y e. v -> (G` y) = (rec({<.z, w>. | w = (F` z)}, x)` y))
3635iuneq2i 2580 . . . . . . 7 |- U_y e. v (G` y) = U_y e. v (rec({<.z, w>. | w = (F` z)}, x)` y)
3732, 33, 363eqtr4g 1531 . . . . . 6 |- (Lim v -> (G` v) = U_y e. v (G` y))
3837adantr 389 . . . . 5 |- ((Lim v /\ A.y e. v (G` y) = x) -> (G` v) = U_y e. v (G` y))
39 iuneq2 2578 . . . . . 6 |- (A.y e. v (G` y) = x -> U_y e. v (G` y) = U_y e. v x)
40 df-lim 2953 . . . . . . . 8 |- (Lim v <-> (Ord v /\ v =/= (/) /\ v = U.v))
41 3simp2 789 . . . . . . . 8 |- ((Ord v /\ v =/= (/) /\ v = U.v) -> v =/= (/))
4240, 41sylbi 199 . . . . . . 7 |- (Lim v -> v =/= (/))
43 iunconst 2572 . . . . . . 7 |- (v =/= (/) -> U_y e. v x = x)
4442, 43syl 10 . . . . . 6 |- (Lim v -> U_y e. v x = x)
4539, 44sylan9eqr 1529 . . . . 5 |- ((Lim v /\ A.y e. v (G` y) = x) -> U_y e. v (G` y) = x)
4638, 45eqtrd 1507 . . . 4 |- ((Lim v /\ A.y e. v (G` y) = x) -> (G` v) = x)
4746ex 373 . . 3 |- (Lim v -> (A.y e. v (G` y) = x -> (G` v) = x))
4847a1d 12 . 2 |- (Lim v -> ((F` x) = x -> (A.y e. v (G` y) = x -> (G` v) = x)))
492, 4, 6, 12, 29, 48tfinds2 3165 1 |- (v e. On -> ((F` x) = x -> (G` v) = x))
Colors of variables: wff set class
Syntax hints:   -> wi 3   /\ wa 223   /\ w3a 775   = wceq 956   e. wcel 958   =/= wne 1585  A.wral 1645  Vcvv 1811  (/)c0 2280  U.cuni 2503  U_ciun 2566  {copab 2666  Ord word 2947  Oncon0 2948  Lim wlim 2949  suc csuc 2950  ` cfv 3182  reccrdg 3931
This theorem is referenced by:  abianfp 3962
This theorem was proved from axioms:  ax-1 4  ax-2 5  ax-3 6  ax-mp 7  ax-7 962  ax-gen 963  ax-8 964  ax-9 965  ax-10 966  ax-11 967  ax-12 968  ax-13 969  ax-14 970  ax-17 971  ax-4 973  ax-5o 975  ax-6o 978  ax-9o 1123  ax-10o 1140  ax-16 1210  ax-11o 1218  ax-ext 1459  ax-rep 2693  ax-sep 2703  ax-nul 2710  ax-pow 2742  ax-pr 2779  ax-un 2866
This theorem depends on definitions:  df-bi 147  df-or 224  df-an 225  df-3or 776  df-3an 777  df-ex 981  df-sb 1172  df-eu 1382  df-mo 1383  df-clab 1464  df-cleq 1469  df-clel 1472  df-ne 1587  df-ral 1649  df-rex 1650  df-rab 1652  df-v 1812  df-sbc 1942  df-dif 2049  df-un 2050  df-in 2051  df-ss 2053  df-nul 2281  df-if 2362  df-pw 2402  df-sn 2412  df-pr 2413  df-tp 2415  df-op 2416  df-uni 2504  df-iun 2568  df-br 2620  df-opab 2667  df-tr 2681  df-eprel 2832  df-id 2835  df-po 2840  df-so 2850  df-fr 2917  df-we 2934  df-ord 2951  df-on 2952  df-lim 2953  df-suc 2954  df-xp 3184  df-rel 3185  df-cnv 3186  df-co 3187  df-dm 3188  df-rn 3189  df-res 3190  df-ima 3191  df-fun 3192  df-fn 3193  df-fv 3198  df-rdg 3932
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